How to have to variable looping at the same time with the same increment?

askmewhy25's Avatar, Join Date: Jan 2010
Go4Expert Member
Here is my problem I can't figure out how to loop two variable at the same
while they increment at the same time with the same increment
I can't explain myself I will just give an example:

Code:
The increment is 50
T1          T2
300         350
350         400
400         450
450         500
500         550
550         600
600         650
650         700
700         750
750         800
800         850
850         900
900         950
950         1000
Here is my program
Code:
#include <stdio.h>
#include <conio.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>

int main(){
  int i,j,T;
  
  printf("Input T: ");
  scanf("%d",&T);
  for(j=300+T;j<=1000;j+=T)
  for(i=300;i<=(1000-T);i+=T){
    printf("T1 = %d and T2 = %d\n",i,j);
    }          
  getche();
}

Last edited by askmewhy25; 5Mar2010 at 12:00..
karthigayan's Avatar, Join Date: Feb 2010
Go4Expert Member
I checked your code in linux machine.so I have changed few lines.

In your code there is no need to two loops.You can do that using a single loop.

Code:
#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>

int main(){
  int i,j,T;

  printf("Input T: ");
  scanf("%d",&T);
    for(i=300;i<=950;i+=T)
    {
            j=i+50;
      printf("T1 = %d and T2 = %d\n",i,j);
    }
}
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techgeek.in's Avatar, Join Date: Dec 2009
Skilled contributor
do this:-
Code:
#include <stdio.h>
#include <conio.h>


int main(){
  int i,j,T;
  
  printf("Input T: ");
  scanf("%d",&T);
  for(i=300,j=350;i<=1000  && j<=1000 ;i+=T,j+=T)
   {
    printf("T1 = %d and T2 = %d\n",i,j);
    }          
  getch();
return 0;
}
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askmewhy25's Avatar, Join Date: Jan 2010
Go4Expert Member
Thanks techgeek.in but i have another question.. if the user wanted to input numbers with decimal numbers how will i do that??
virxen's Avatar, Join Date: Nov 2009
Pro contributor
Code:
#include <stdio.h>

int main(){
    float T1,T2,end1,increment;
    printf("first variable=");
    scanf("%f",&T1);
    printf("second variable=");
    scanf("%f",&T2);
    printf("increment for first and second variable=");
    scanf("%f",&increment);
    printf("end when first variable is>=");
    scanf("%f",&end1);
    printf("The increment is %f",increment);
        printf("\n     T1              T2\n");
    while(T1<end1){
        T1+=increment;
        T2+=increment;
        printf("%10.3f      %10.3f\n",T1,T2);
    }
    getchar(); getchar();
}
with this code you can have T1,T2 and increment as demical numbers

Last edited by virxen; 5Mar2010 at 13:30..
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techgeek.in's Avatar, Join Date: Dec 2009
Skilled contributor
u can try this:-
Code:
#include <stdio.h>
#include <conio.h>


int main(){
  float i,j,T;
  
  printf("Input T: ");
  scanf("%f",&T);
  for(i=300.0,j=350.0;i<=1000.0  && j<=1000.0 ;i+=T,j+=T)
   {
    printf("T1 = %f and T2 = %f\n",i,j);
    }          
  getch();
  return 0;
}
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askmewhy25's Avatar, Join Date: Jan 2010
Go4Expert Member
Now I upgraded the program.. thanks to all your help!! but i have a last question
how can I set the range or the stopper to T2 to 1000K because the table of the ideal
gas is for only 300K to 1000K so beyond that range in not applicable..

Code:
//This program generates a table for the specific internal energy
//and the specific enthalpy of Methane from 300K to 1000K using the
//specific heat variations listed on Table A.21

#include <stdio.h>
#include <conio.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>

int main(){
  int QA;
  float T1=300,T2,end1,inc;
  double a=3.826,b=-3.979,c=24.558,d=-22.733,e=6.963;
  double A,B,C,D,E,H,U,R=8.3143,M=16.04,i=10;
  char error[128];
  
  do{
  do{
    system("cls");
    printf("Enter the Increment in Temperature: ");
    scanf("%s",&error);
    inc=atof(error);
    if(inc<=0){
      system("cls");
      printf("Invalid Input. Please try again!!!\n");
      printf("Please press the spacebar to continue!!");
      getche();
      }
    }while(inc<=0);
  T2=T1+inc;
  end1=1000-inc;
  printf("The increment is %.3f\n\n",inc);
  printf("\nInitial Temperature\tFinal Temperature\tEnthalpy\tInternal Energy\n");
  while(T1<=end1){
    T1+=inc;
    T2+=inc;
    A=a*(T2-T1);
    B=(1/pow(i,3))*(b/2)*(pow(T2,2)-pow(T1,2));
    C=(1/pow(i,6))*(c/3)*(pow(T2,3)-pow(T1,3));
    D=(1/pow(i,9))*(d/4)*(pow(T2,4)-pow(T1,4));
    E=(1/pow(i,12))*(e/5)*(pow(T2,5)-pow(T1,5));
    H=(R/M)*(A+B+C+D+E);
    U=(R/M)*((A+B+C+D+E)-(T2-T1));
    printf("%10.3f K\t\t%10.3f K\t\t%.3f kJ/kg\t%.3f kJ/kg\n",T1,T2,H,U);
    }
  do{//This used to ask the user if s/he wants to repeat the evaluation
    printf("\n\nDo you want to repeat the computation or Quit?\n");
    printf("[1] Yes\n");
    printf("[2] Quit\n");
    scanf("%s",&error);
    QA=atoi(error);
    switch(QA){
      case 1:
        break;
      case 2://Return to the selection screen
        exit(1);
        break;
      default://The program redirects invalid inputs to this part
        system("cls");
        printf("Invalid input. Please try again!!!\n");
        printf("Please press the spacebar to continue!!");
        getche();
        break;   
        }
      }while(QA>2||QA<1);
    }while(QA==1);         
  getche();
}
techgeek.in's Avatar, Join Date: Dec 2009
Skilled contributor
see this:-
Code:
//This program generates a table for the specific internal energy
//and the specific enthalpy of Methane from 300K to 1000K using the
//specific heat variations listed on Table A.21

#include <stdio.h>
#include <conio.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>

int main(){
  int QA;
  float T1=300,T2,end1,inc;
  double a=3.826,b=-3.979,c=24.558,d=-22.733,e=6.963;
  double A,B,C,D,E,H,U,R=8.3143,M=16.04,i=10;
  char error[128];
  
  do{
  do{
    system("cls");
    printf("Enter the Increment in Temperature: ");
    scanf("%s",&error);
    inc=atof(error);
    if(inc<=0){
      system("cls");
      printf("Invalid Input. Please try again!!!\n");
      printf("Please press the spacebar to continue!!");
      getche();
      }
    }while(inc<=0);
  T2=T1+inc;
  end1=1000-inc;
  printf("The increment is %.3f\n\n",inc);
  printf("\nInitial Temperature\tFinal Temperature\tEnthalpy\tInternal Energy\n");
  while(T1<=end1){
    T1+=inc;
    T2+=inc;
    A=a*(T2-T1);
    B=(1/pow(i,3))*(b/2)*(pow(T2,2)-pow(T1,2));
    C=(1/pow(i,6))*(c/3)*(pow(T2,3)-pow(T1,3));
    D=(1/pow(i,9))*(d/4)*(pow(T2,4)-pow(T1,4));
    E=(1/pow(i,12))*(e/5)*(pow(T2,5)-pow(T1,5));
    H=(R/M)*(A+B+C+D+E);
    U=(R/M)*((A+B+C+D+E)-(T2-T1));
    printf("%10.3f K\t\t%10.3f K\t\t%.3f kJ/kg\t%.3f kJ/kg\n",T1,T2,H,U);
    }
  do{//This used to ask the user if s/he wants to repeat the evaluation
    printf("\n\nDo you want to repeat the computation or Quit?\n");
    printf("[1] Yes\n");
    printf("[2] Quit\n");
    scanf("%s",&error);
    QA=atoi(error);
    switch(QA){
      case 1:
        break;
      case 2://Return to the selection screen
        exit(1);
        break;
      default://The program redirects invalid inputs to this part
        system("cls");
        printf("Invalid input. Please try again!!!\n");
        printf("Please press the spacebar to continue!!");
        getche();
        break;   
        }
      }while(QA>2||QA<1);
    }while(QA==1 && T2<=1000);         
  getche();
}
virxen's Avatar, Join Date: Nov 2009
Pro contributor
Quote:
Originally Posted by techgeek.in View Post
see this:-
Code:
//This program generates a table for the specific internal energy
//and the specific enthalpy of Methane from 300K to 1000K using the
//specific heat variations listed on Table A.21

#include <stdio.h>
#include <conio.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>

int main(){
  int QA;
  float T1=300,T2,end1,inc;
  double a=3.826,b=-3.979,c=24.558,d=-22.733,e=6.963;
  double A,B,C,D,E,H,U,R=8.3143,M=16.04,i=10;
  char error[128];
  
  do{
  do{
    system("cls");
    printf("Enter the Increment in Temperature: ");
    scanf("%s",&error);
    inc=atof(error);
    if(inc<=0){
      system("cls");
      printf("Invalid Input. Please try again!!!\n");
      printf("Please press the spacebar to continue!!");
      getche();
      }
    }while(inc<=0);
  T2=T1+inc;
  end1=1000-inc;
  printf("The increment is %.3f\n\n",inc);
  printf("\nInitial Temperature\tFinal Temperature\tEnthalpy\tInternal Energy\n");
  while(T1<=end1){
    T1+=inc;
    T2+=inc;
    A=a*(T2-T1);
    B=(1/pow(i,3))*(b/2)*(pow(T2,2)-pow(T1,2));
    C=(1/pow(i,6))*(c/3)*(pow(T2,3)-pow(T1,3));
    D=(1/pow(i,9))*(d/4)*(pow(T2,4)-pow(T1,4));
    E=(1/pow(i,12))*(e/5)*(pow(T2,5)-pow(T1,5));
    H=(R/M)*(A+B+C+D+E);
    U=(R/M)*((A+B+C+D+E)-(T2-T1));
    printf("%10.3f K\t\t%10.3f K\t\t%.3f kJ/kg\t%.3f kJ/kg\n",T1,T2,H,U);
    }
  do{//This used to ask the user if s/he wants to repeat the evaluation
    printf("\n\nDo you want to repeat the computation or Quit?\n");
    printf("[1] Yes\n");
    printf("[2] Quit\n");
    scanf("%s",&error);
    QA=atoi(error);
    switch(QA){
      case 1:
        break;
      case 2://Return to the selection screen
        exit(1);
        break;
      default://The program redirects invalid inputs to this part
        system("cls");
        printf("Invalid input. Please try again!!!\n");
        printf("Please press the spacebar to continue!!");
        getche();
        break;   
        }
      }while(QA>2||QA<1);
    }while(QA==1 && T2<=1000);         
  getche();
}
correct the above code like this

Code:
.......................
    switch(QA){
      case 1:
            T1=300;//add this
            T2=0;//add this
        break;
      case 2://Return to the selection screen
        exit(1);
......................
Code:
}while(QA>2||QA<1);
    }while(QA==1 && T2<=1000); //i am not sure but i think you must remove =        
  getche();
}
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askmewhy25's Avatar, Join Date: Jan 2010
Go4Expert Member
I figured it out already..hehe the only thing that is needed to be change is this

Code:
  T1=300-inc;
  T2=300;
  end1=1000-inc;
Program
Code:
//This program generates a table for the specific internal energy
//and the specific enthalpy of Methane from 300K to 1000K using the
//specific heat variations listed on Table A.21

#include <stdio.h>
#include <conio.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>

int main(){
  int QA;
  float T1=300,T2,end1,inc;
  double a=3.826,b=-3.979,c=24.558,d=-22.733,e=6.963;
  double A,B,C,D,E,H,U,R=8.3143,M=16.04,i=10;
  char error[128];
  
  do{
  do{
    system("cls");
    printf("Enter the Increment in Temperature: ");
    scanf("%s",&error);
    inc=atof(error);
    if(inc<=0){
      system("cls");
      printf("Invalid Input. Please try again!!!\n");
      printf("Please press the spacebar to continue!!");
      getche();
      }
    }while(inc<=0);
  T2=T1+inc;
  end1=1000-inc;
  printf("The increment is %.3f\n\n",inc);
  printf("\nInitial Temperature\tFinal Temperature\tEnthalpy\tInternal Energy\n");
  while(T1<=end1){
    T1+=inc;
    T2+=inc;
    A=a*(T2-T1);
    B=(1/pow(i,3))*(b/2)*(pow(T2,2)-pow(T1,2));
    C=(1/pow(i,6))*(c/3)*(pow(T2,3)-pow(T1,3));
    D=(1/pow(i,9))*(d/4)*(pow(T2,4)-pow(T1,4));
    E=(1/pow(i,12))*(e/5)*(pow(T2,5)-pow(T1,5));
    H=(R/M)*(A+B+C+D+E);
    U=(R/M)*((A+B+C+D+E)-(T2-T1));
    printf("%10.3f K\t\t%10.3f K\t\t%.3f kJ/kg\t%.3f kJ/kg\n",T1,T2,H,U);
    }
  do{//This used to ask the user if s/he wants to repeat the evaluation
    printf("\n\nDo you want to repeat the computation or Quit?\n");
    printf("[1] Yes\n");
    printf("[2] Quit\n");
    scanf("%s",&error);
    QA=atoi(error);
    switch(QA){
      case 1:
        break;
      case 2://Return to the selection screen
        exit(1);
        break;
      default://The program redirects invalid inputs to this part
        system("cls");
        printf("Invalid input. Please try again!!!\n");
        printf("Please press the spacebar to continue!!");
        getche();
        break;   
        }
      }while(QA>2||QA<1);
    }while(QA==1);         
  getche();
}